Installing the Approvals app on your Zendesk is easy. First, you'll need to go to the Zendesk apps marketplace which you'll find by first logging into Zendesk and then clicking the cog on the left side of the screen, then click on "Marketplace" under "Apps" at the top.
Next, do a search for "approvals" and click on the Approvals app...
On the right-hand side, click on "Buy".
Then back in your Zendesk account, click on the "Buy" button again like this:
Finally put in your credit card details, agree to the terms and conditions and click "Pay Now". Note, that while the Zendesk doesn't have in-built trial functionality, we do - so even though it says you're "paying now", we won't actually bill for the first 14 days - so you've got plenty of time to try the app out, risk-free :-)
Once you've successfully installed the app, you should check out the next article on how to use it here: https://support.sweethawk.co/hc/en-us/articles/231983548-How-to-use-the-Approvals-app